Installation guide

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Wi-Fi Location-Based Services—Design and Deployment Considerations
OL-11612-01
Cisco Location-Based Services Architecture
• SOAP/XML Location Application Programming Interface (API)—The Location Appliance API
allows customers and partners to create customized location-based programs that interface with the
Cisco Wireless Location Appliance. These programs can be developed to support a variety of unique
and innovative applications including real-time location-based data retrieval, telemetric device
management, workflow automation, enhanced WLAN security, and people or device tracking. The
API provides a mechanism for inserting, retrieving, updating, and removing data from the Cisco
Wireless Location Appliance configuration database using a SOAP/XML interface. Developers can
access the Cisco Wireless Location Appliance provisioning services using XML and exchange data
in XML format. The location appliance API is available and licensable to the Cisco development
community along with tools to facilitate solution development. Integration support is available via
the Cisco Developer Services Program, a subscription-based service.
Note For complete details, see the following URL: http://www.cisco.com/go/developersupport.
Location Tracking without a Location Appliance
To use any RF Fingerprinting-based location tracking solutions in a Cisco LWAPP-based wireless LAN,
a version of WCS that is licensed for use with the Cisco Wireless Location Server is required. When a
location appliance is not used as part of the solution, RF Fingerprinting location tracking services are
available only as an on-demand service and only for a single device at a time. In addition, there is no
historical trending of data nor any capability to interface to external third-party applications via the
SOAP/XML API without the use of a location appliance.
If only base WCS functionality has been licensed (WCS-Base), WCS provides a basic set of location
services that does not employ RF Fingerprinting for localization. In this case, on-demand location for a
single device is performed based on the access point that is detecting the mobile device with the highest
signal strength (see Cell of Origin, page 7 and Figure 2). The Cisco Wireless Location Appliance cannot
be used with WCS when only base WCS functionality has been licensed (WCS must be licensed for
location, otherwise referred to as WCS-Location).
Further information regarding the basic location capabilities of WCS can be found in the “WLAN
Management” chapter of the Cisco Unified Wireless Network Solutions Design Guide v3.0.
Solution Performance
The Meaning of Accuracy and Precision
For most users, the performance metric having the most familiarity and significance is accuracy, which
typically refers to the quality of the information you are receiving. Location accuracy refers specifically
to the quantifiable error distance between the estimated location and the actual location of the mobile
device.
In most real-world applications, however, a statement of location accuracy has little value without the
ability of the solution to repeatedly and reliably perform at this level. Precision is a direct measure
reflecting on the reproducibility of the stated location accuracy. Any indication of location accuracy
should therefore include an indication of the confidence interval or percentage of successful location
detection as well, otherwise known as the location precision.